Evacuation travel assist apparatus

ABSTRACT

An evacuation travel assist apparatus includes a stop lane determination section that determines a stop lane and an evacuation place in the stop lane in which an own vehicle should be urgently stopped when the vehicle drive is detected to be in a state of being not able to drive the own vehicle properly, and a transverse position determination section that determines, as a stop transverse position, a position in a transverse direction of the evacuation place in the stop lane so as to ensure a space for the vehicle driver and passengers to get in and out of the own vehicle safely at a side of the own vehicle.

This application claims priority to Japanese Patent Application No.2015-84314 filed on Apr. 16, 2015, and is a divisional application ofU.S. patent application Ser. No. 15/097,678 filed on Apr. 13, 2016, theentire contents of which are hereby incorporated by reference.

BACKGROUND OF THE INVENTION 1. Field of the Invention

The present invention relates to a technique for evacuating an ownvehicle upon detecting reduction of consciousness of the driver of theown vehicle.

2. Description of Related Art

There is known a technique for evacuating an own vehicle to a roadshoulder area using a travel assist system to secure the safety of theown vehicle and other vehicles when the level of the consciousness ofthe driver of the own vehicle is reduced due to drowsiness, for example,or the driver has lost the consciousness for some reason. For example,refer to Japanese Patent Application Laid-open No. 2007-331652.

However, since this technique places importance on avoiding the ownvehicle from obstructing the travel of other vehicles in determining aplace for evacuation, there may occur a problem that the own vehicle maybe parked at a place in which a guardrail or a wall is present andaccordingly it is difficult to let a sick person exit from the ownvehicle or difficult for the passengers to get out of the own vehicle.

SUMMARY

An exemplary embodiment provides an evacuation travel assist apparatusincluding:

a driver-state determination section that determines whether or not avehicle driver of an own vehicle is in a state of being able to drivethe own vehicle properly;

an information acquisition section that acquires information regarding astate of the own vehicle and a state of a surrounding environment of theown vehicle;

a stop lane determination section that determines a stop lane and anevacuation place in the stop lane, in which the own vehicle should beurgently stopped based on the information acquired by the informationacquisition section when the driver-state determination sectiondetermines that the vehicle drive is not in a state of being able todrive the own vehicle properly;

a transverse position determination section that determines, as a stoptransverse position, a position in a transverse direction of theevacuation place in the stop lane so as to ensure a space for thevehicle driver and passengers to enter and exit the own vehicle safelyat a side of the own vehicle; and

an evacuation travel control section that causes the own vehicle totravel to the evacuation place depending on the stop lane determined bythe stop lane determination section and the stop transverse positiondetermined by the transverse position determination section.

According to the exemplary embodiment, there is provided an evacuationtravel assist apparatus that enables causing a vehicle to travel to anevacuation place in which the vehicle driver and passengers can get inand out of safely without obstructing the travel of other vehicles.

Other advantages and features of the invention will become apparent fromthe following description including the drawings and claims.

BRIEF DESCRIPTION OF THE DRAWINGS

In the accompanying drawings:

FIG. 1 is a block diagram showing the structure of an evacuation travelassist apparatus according to an embodiment of the invention and thestructure of an apparatus which cooperates with the evacuation travelassist apparatus;

FIG. 2 is a flowchart showing steps of an evacuation route settingprocess performed by the evacuation travel assist apparatus;

FIG. 3 is a diagram showing a stop transverse position when there is anadjacent lane (a parallel lane) on one side of a stop lane;

FIG. 4 is a diagram showing a stop transverse position when there is anadjacent lane (an opposite lane) on one side of a stop lane;

FIG. 5 is a diagram showing a stop transverse position when there is noadjacent lane in either side of a stop lane, and there is an obstacle togetting on and off at the end of a driveway apron;

FIG. 6 is a diagram showing a stop transverse position when there is noadjacent lane in either side of a stop lane, and there is no obstacle togetting on and off; and

FIG. 7 is a diagram showing a stop transverse position when there is anadjacent lane at each side of a stop lane.

PREFERRED EMBODIMENTS OF THE INVENTION

An evacuation travel assist apparatus 1 according to an embodiment ofthe invention is described with reference to the drawings. Theevacuation travel assist apparatus 1 shown in FIG. 1 is for assisting avehicle driver to drive a vehicle (referred to as the “own vehicle”hereinafter) to a safe evacuation place and park the own vehicle therein cooperation with a drive assist system 2 mounted on the own vehicleif the vehicle driver is assumed not to be in a state of being able toproperly drive the own vehicle.

The drive assist system 2 includes an all-speed ACC (adaptive cruisecontrol) device 21, an LKA (lane keep assist) control device 22, an LCA(lane change assist) control device 23 and other drive assist controldevices 24. The drive assist control devices 24 may include an anti-lockbrake system, a collision damage reducing system, or a stability controlsystem.

These control devices 21 to 24 constituting the drive assist system 2are implemented as ECUs, and are connected to the evacuation travelassist apparatus 1 through an in-vehicle LAN. Normally, the controldevices 21 to 24 operate in accordance with instructions or drivingoperation of the vehicle driver. However, when they receive instructionsregarding evacuation travel from the evacuation travel assist apparatus1, they operate in accordance with these instructions. For example, thecontrol devices 21 to 24 perform data calculation necessary fordeceleration control, lane keep control, lane change control orcollision prevention control taking into account the speed of the ownvehicle, road alignment, presence or absence of a succeeding vehicle andso on. The drive assist system 2 controls various control objects basedon the results of the data calculation so that the acceleration control,brake control and steering control are performed for each of the controlobjects to achieve desired motion control of the own vehicle. Since thevarious control devices constituting the drive assist system 2 are wellknown, further explanations of them are omitted here.

Next, the evacuation travel assist apparatus 1 is described. Theevacuation travel assist apparatus 1 includes a map informationacquisition section 11, an own-vehicle information acquisition section12, a surrounding environment information acquisition section 13, adriver information acquisition section 14, a driver-state determinationsection 15, an evacuation route setting section 16 and an evacuationtravel control section 17.

The map information acquisition section 11 acquires map information foran area which the own vehicle may run through. The map informationincludes a road alignment information (a curvature and a slope and theirchange pints, for example), lane information (the number of lanes, andlane type such as a traveling lane, a passing lane, a climbing lane, anevacuation route, a road shoulder, a left turn or right turn lane, amerging lane, an exit lane and so on), junction point information (anintersection, a junction, a crosswalk, a railroad crossing and so on),and road boundary information(a guard rail, a wall, a side ditch, apole, a block, a fence, a cliff and so on). Such map information may bestored in a storage device in the own vehicle, and/or acquired fromoutside the own vehicle through data communication.

The own-vehicle information acquisition section 12 acquires, asown-vehicle information, information regarding the state of the ownvehicle. The own-vehicle information includes information regarding theoperation state of the direction indicator, vehicle speed, vehicleacceleration (deceleration) and operation amount of steering of the ownvehicle, which can be obtained from sensor signals of a directionindicator sensor, a speed sensor, an acceleration sensor and steeringangle sensor, respectively.

The surrounding environment information acquisition section 13 acquires,as surrounding environment information, information regarding objectspresent around the own vehicle. The surrounding environment informationincludes information regarding a distance to each object, a relativespeed of each object, a current position of each object and so on whichcan be obtained by an image sensor, a radar sensor, a GPS sensor, alocator and so on. The surrounding environment information includes alsovarious information (the number of the lanes and the lane in which theown vehicle is running, for example) which can be obtained byimage-processing images supplied from an image sensor.

The driver information acquisition section 14 acquires, as driverinformation, information used for determining whether the vehicle driveris in a state of being able to drive the own vehicle properly. Thedriver information includes information regarding the feature quantityof the face or eyes of the vehicle driver which can be extracted fromimages of the vehicle driver imaged by a camera, for example, thesteering angle which directly reflects the driving operation by thevehicle driver and is detected by the steering angle sensor, andbiological information such as the blood pressure and the bodytemperature of the vehicle driver obtained by sensors worn by thevehicle driver.

The driver-state determination section 15 determines whether or not thevehicle driver is in a state of being able to drive the vehicle properlyby estimating the level of the consciousness of the vehicle driver basedon the driver information acquired by the driver information acquisitionsection 14.

The evacuation route setting section 16 sets an evacuation place atwhich the own vehicle should be stopped and parked and an evacuationroute along which the own vehicle should travel to reach the evacuationplace.

The evacuation travel control section 17 generates instructions inaccordance with the evacuation place, the transverse position of theevacuation place in an evacuation lane or a lane in which the evacuationplace is set, and the evacuation route set by the evacuation routesetting section 16. These instructions are sent to the drive assistsystem 2 to perform evacuation control.

The evacuation travel assist apparatus 1 is formed of a microcomputerincluding a CPU, memories and so on. The functions of the abovedescribed various control sections are implemented by software run bythis microcomputer.

Next, an evacuation route setting process performed by the evacuationroute setting section 16 is explained with reference to the flowchart ofFIG. 2. This process is started when the driver-state determinationsection 15 determines that the vehicle driver is in a state of not beingable to drive the own vehicle properly and an evacuation travel isnecessary.

This process begins in step S110 where the evacuation route settingsection 16 identifies the lane in which the own vehicle is running (therunning lane hereinafter) and sets a plurality of candidate evacuationplaces taking into account various risks based on the map informationacquired by the map information acquisition section 11, the own-vehicleinformation acquired by the own-vehicle information acquisition section12 and the surrounding environment information acquired by thesurrounding environment information acquisition section 13.Specifically, the evacuation route setting section 16 marks out aplurality of spots within an area in which the own vehicle may run foreach lane and for each of predetermined distances, and evaluates risklevels of these spots in terms of a plurality of different viewpoints,and determines a plurality of candidate evacuation places which haverelatively low risk levels. The risks to be evaluated in determining thecandidate evacuation places includes a risk which depends on a roadshape (a curved road, an intersection and so on) and the environment(presence of a guard rail or protective wall, for example), a risk thatoccurs when the own vehicle is stopped (for example, a passing lane anda curved lane with a poor view are risky), and a risk of continuing anevacuation travel for a long time.

In subsequent step S120, an evacuation place and an evacuation route aredetermined based on the map information, the own-vehicle information andthe surrounding environment information taking into account potentialrisks to reach the candidate evacuation places determined in step S110.Specifically, for each of the candidate evacuation places, an optimumroute that is lowest in the risk level to reach the candidate evacuationplace is detected. Then, one of the candidate evacuation places, whoseoptimum route is the lowest in the risk level, is determined as anevacuation place, and the optimum route to this determined evacuationplace is determined as an evacuation route. The risks to be consideredin determining the evacuation place and the evacuation route includes arisk of route change (abrupt route change or route change in a curvedroad is risky), and a risk of making a stop (a place which requiresheavy braking to stop is risky).

The technique for determining such an evacuation place and an evacuationroute based on the risk levels is described in detail, for example, inJapanese Patent Application Laid-open No. 2014-112900. Accordingly,further detailed explanation of this technique is omitted.

In subsequent step S130, it is determined whether or not there areadjacent lanes on both sides of the evacuation lane (the lane in whichthe evacuation place determined in step S120 is present). If thedetermination result in step S130 is affirmative, the process proceedsto step S140, and otherwise proceeds to step S150. Here, the adjacentlanes include the own lane (the lane in which the own vehicle isrunning) and the opposite lane. However, if the own vehicle cannot runinto the opposite lane due to a median strip or the like, this oppositelane is not regarded as the adjacent lane.

In step S140, a position in the width direction in the evacuation laneat which the own vehicle should be stopped (this position being referredto as the “stop transverse position” hereinafter) is set at the centerof the evacuation lane. Then, this process is terminated. In step S150,it is determined whether or not there is an adjacent lane only on oneside of the evacuation lane. If the determination result in step S150 isaffirmative, the process proceeds to step S160, and otherwise proceedsto step S170.

In step S160, a position in which a space of a required size for gettingon and off the own vehicle can be ensured between the own vehicle andthe edge of the evacuation lane on the side where there is no adjacentlane is set as the stop transverse position. Then, this process isterminated.

The required size of the space for getting on and off the own vehicle isset depending on the door type of the own vehicle (hinge type or slidetype, for example). In step S170, it is determined whether or not anobstacle to getting on and off is present on the left edge of theevacuation lane. The obstacle to getting on and off may be an artificialconstruction such as a guard rail or a wall, or a natural obstacle suchas a cliff.

If the determination result in step S170 is affirmative, the processproceeds to step S180, and otherwise proceeds to step S190. In stepS180, a position in which a space for getting on and off the own vehiclecan be ensured between the own vehicle and the left edge of theevacuation lane is set as the stop transverse position. Then, thisprocess is terminated.

In step S190, a position in which a space for getting on and off the ownvehicle can be ensured between the own vehicle and the right edge of theevacuation lane is set as the stop transverse position. Then, thisprocess is terminated. According to the evacuation travel assistapparatus 1 described above, when an adjacent lane is present only onone side of the evacuation lane, a position in which a space for gettingon and off the own vehicle can be ensured between the own vehicle andthe edge of the evacuation lane on the side opposite to the adjacentlane is set as the stop transverse position as shown in FIGS. 3 and 4.That is, when an adjacent lane is present, it is possible to ensure aspace for getting on and off the own vehicle while ensuring a space forother vehicles to run. In this case, the driver and passengers can getin and out of the own vehicle safely without obstructing the travel ofother vehicles.

When an adjacent lane is not present on either side of the evacuationlane, and an obstacle is present on the left edge of the evacuationlane, the stop transverse position is set giving priority to ensuring aspace for getting on and off the own vehicle as shown in FIG. 5. On theother hand, when an adjacent lane is not present on either side of theevacuation lane, and no obstacle to getting and off the own vehicle ispresent on the left edge of the evacuation lane, the stop transverseposition is set giving priority to ensuring a space for other vehiclesto run as shown in FIG. 6. This is because, when no obstacle to gettingand off the own vehicle is present on the left edge of the evacuationlane, even if the own vehicle is pulled to the left edge of theevacuation lane and parked there, the vehicle driver and passengers ofthe own vehicle can get in and out of the own vehicle easily. In asituation where the driver and passengers can get in and out of the ownvehicle without difficulty although a sufficient space for getting onand off cannot be ensured, since a space for other vehicle to run isensured with priority, it is possible to prevent obstructing othervehicle from running.

In a rare case where adjacent lanes are present on both side of theevacuation lane, the center of the evacuation lane is set as the stoptransverse position. This is because if adjacent lanes are present onboth sides of the evacuation lane, a space forgetting on and off the ownvehicle and a space for other vehicles to run can be ensured withoutpulling the own vehicle to one edge of the evacuation lane.

Other Embodiments

It is a matter of course that various modifications can be made to theabove described embodiment as described below.

In the above embodiment, the evacuation place and evacuation route aredetermined taking into account the various risks. However, a placesatisfying predetermined criteria within a predetermined distance fromthe own vehicle may be determined as the evacuation place.

The above explained preferred embodiments are exemplary of the inventionof the present application which is described solely by the claimsappended below. It should be understood that modifications of thepreferred embodiments may be made as would occur to one of skill in theart.

What is claimed is:
 1. An evacuation travel assist apparatus comprising:a driver-state determination section that determines whether or not avehicle driver of an own vehicle is in a state of being able to drivethe own vehicle properly; an information acquisition section thatacquires information regarding a state of the own vehicle and a state ofa surrounding environment of the own vehicle; a stop lane determinationsection that determines a stop lane and an evacuation place in the stoplane, in which the own vehicle should be urgently stopped based on theinformation acquired by the information acquisition section when thedriver-state determination section determines that the vehicle drive isnot in a state of being able to drive the own vehicle properly; atransverse position determination section that determines, as a stoptransverse position, a position in a transverse direction of theevacuation place in the stop lane so as to ensure a space for thevehicle driver and passengers to enter and exit the own vehicle safelyat a side of the own vehicle; and an evacuation travel control sectionthat causes the own vehicle to travel to the evacuation place dependingon the stop lane determined by the stop lane determination section andthe stop transverse position determined by the transverse positiondetermination section, wherein, when an adjacent lane is present on oneside of the stop lane, the transverse position determination sectiondetermines, as the stop transverse position, a position which is betweenthe own vehicle and an edge opposite to the adjacent lane of the stoplane and in which a space for getting on and off the own vehicle isensured, and wherein, when no adjacent lane is present on either side ofthe stop lane, and an obstacle to getting on and off the own vehicle ispresent on a left edge of the stop lane, the transverse positiondetermination section determines, as the stop transverse position, aposition which is between the own vehicle and a left edge of the stoplane and in which a space for getting on and off the own vehicle isensured.
 2. The evacuation travel assist apparatus according to claim 1,wherein, when no obstacle to getting on and off the vehicle is present,the evacuation travel control section causes the own vehicle to travelto an evacuation place where space for other vehicles to run is presentcan be secured.
 3. The evacuation travel assist apparatus according toclaim 1, wherein, when adjacent lanes are present on both sides of theevacuation lane, the evacuation travel control section causes the ownvehicle to stop in the center of the evacuation lane.
 4. The evacuationtravel assist apparatus according to claim 1, wherein, the evacuationplace is a space for getting on and off the own vehicle can be secured,and the evacuation place changes depending on door type of the ownvehicle.